Many electronic devices are available for use in automobiles. In addition to built-in devices, such as stereo systems, other devices (e.g., CD players, MP3 players, video players, police radar detectors, navigation devices, etc.) may be used by employing a power adapter that plugs into the cigarette lighter socket of the vehicle.
When utilizing such devices, it is common to activate certain features by actuating the control switches contained on the housings of the devices. When the device is mounted on a windshield or visor, the actuation of these switches can be cumbersome. Some motor vehicles have a long, sweeping, dashboard, which forces drivers to possibly overextend their reach in order to activate the device's controls.
To overcome this problem some attempt has been made to incorporate device functions directly into the power cord. For example, one cigarette lighter plug power cord designed for use with a radar detector contains an alert LED, and a power LED on the plug housing and a dedicated switch for controlling the mute and volume functions, allowing the user to activate that function without overreaching. The cord thus provides feature convenience more accessible than utilizing the same switch on the radar detector housing itself. However, the functions that can be activated via the power cord are not programmable. Therefore, if the user desires to activate a function other than the dedicated one (e.g., mute), the user must still reach for the detector's control buttons.
Furthermore, currently available cords utilize a multi-conductor cable and a unique connector for engagement with the mating connector on their products, as depicted in FIG. 3. This four-conductor, telephone-type connector and cable serve as power, ground, LED status indicator, and mute function. A similarly configured “hardwire” kit is also available for bypassing the cigarette lighter plug and wiring the source to the fuse block or other suitable location and contains the same multi-conductor cable to mate with existing products. These cable and connector configurations are considerably more costly than the common two-conductor plug (power and ground) that are typically used for automotive power supplies for many other consumer products.
Therefore it would be desirable to have a cigarette plug power source for electronic devices that comprises a switch that is programmable for a plurality of functions and utilizes a common two-conductor plug.